1. Field of the Invention
The present invention generally relates to a process that copolymerizes two or more polymerizable olefins, and to a metal-ligand complex (precatalyst) and catalyst useful in such process, and to related compositions of matter, and to copolymers prepared thereby. The present invention also generally relates to ligands and intermediates useful for preparing the metal-ligand complex and to processes of their preparation. Other related inventions are described herein.
2. Description of Related Art
Polyolefins are widely used in industry. They are desirable for making, for example, containers, tubing, films and sheets for packaging, and synthetic lubricants. Examples of types of polyolefins are polyethylene polymers, poly(ethylene alpha-olefin) copolymers, and mixtures or blends of such polyolefins. Examples of commercially available polyethylene-containing polyolefins (includes mixtures or blends) are those that are commercially available from The Dow Chemical Company under the trade names DOWLEX, ATTANE, AFFINITY, ELITE, Unipol DFDA-7441 polymer, or Tuflin HS-7028; those that are available from Exxon Chemical Corporation under the trade names EXCEED and EXACT; those that are available from Mitsui Petrochemical Industries under the trade name TAFMER; those that are available from Equistar, Inc. under the trade name Petrothene GA501020 polymer; and those that are available from Nova Chemicals Corporation under the trade name Novapol TF-0 I 19-FP.
The polyolefins are prepared by a catalyzed reaction. Especially desirable would be precatalysts and catalysts that would be soluble in alkane or cycloalkane solvents so that the solutions could be used in the catalyzed reaction for preparing polyolefins acceptable for use in the food packing industry. This is there are concerns in the art about detrimental health and environmental affects of other solvents such as aromatic hydrocarbons and halogenated solvents. It has been difficult, however, to discover such a (pre)catalyst that would have activity at high reaction temperature, high comonomer incorporation into ethylene/(alpha-olefin copolymers (e.g., poly(ethylene-co-1-octene)copolymers) and solubility in alkane or cycloalkane solvents.
U.S. Pat. No. 7,241,714 B2 mentions, among other things, ligands, compositions, metal-ligand complexes and arrays with substituted bridged bis-aromatic groups that are useful for preparing ethylene/olefin copolymers. The patent also mentions methods of making and using the same in the catalysis of transformations such as the polymerization of monomers into polymers. Unfortunately, these bis(phenyl phenol)-type ligands, compositions, metal-ligand complexes and arrays do not combine high temperature activity and high comonomer incorporation and, preferably, alkane or cycloalkane solubility in one catalyst.
Chemical industry desires improved processes and catalysts for copolymerizing two or more polymerizable olefins, and improved polyolefins prepared thereby.